Design Issues in the Go2 Grid System

Val Noronha


Digital Geographic Research Corporation
Mississauga, Ontario, Canada
Santa Barbara, California

Email: noronha@dgrc.ca


The Go2 vision brings a system of geographic coordinates into public use for the first time. This is a big step forward for location science, and while it presents opportunities, it raises several challenges in terms of comprehension, usability, consequences of misuse, and even legal liability. For example, because the system is "overtiled," there is a many to one mapping of Go2 addresses to real world locations. Second, although the map projection provides for addresses to be specified in meaningful distance units, the multiplicity of projection centers results in grid discontinuity. Third, both the alphabetic and numeric components of an address contain potential for error, confusion and misunderstanding. This presentation examines these technical issues in depth, and discusses approaches we are pursuing in system design to minimize problems. It covers the choice of map projection, handling of overtiling, design and assignment of alphabetic codes, and error-proofing for mission critical application.